A Closer Look at the AMPKinase Signaling Pathway

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Figure 1. AMP Kinase signaling pathway (AMPK Signaling Pathway 2014).

AMP Kinase is activated under conditions such as low glucose levels and hypoxia that put stress on cells by depleting the cellular ATP (AMPK Signaling Pathway 2014). When active AMPK positively regulates signaling pathways that bring ATP levels back to homeostatic levels by inducing fatty acid oxidation and autophagy. When active this pathway turns off ATP-consuming biosynthetic processes including gluconeogenesis and synthesis of lipids and proteins.This happens by AMPK phosphorylating enzymes that are involved in the gluconeogenesis process as well as through transcriptional control of metabolism by activating transcription factors, co-activators and co-repressors. Additionally, when cAMP concentrations are high it will activate PKA which turns on LKB1 which activates AMPK (AMPK Signaling Pathway 2014). When ATP levels are low and a AMPK is active it increases TSC2 transcription which is an inhibitor of mTOR (mTOR Signaling Pathway 2014).